This application claims priority under 35 U.S.C. .sctn. 119 of European Patent Application No. 97202661.1, filed in the European Patent Office on Aug. 29, 1997, which is incorporated herein by reference in its entirety for all purposes.
The invention relates to a catheter with a first component, a second component, and a glue line, which is filled with an adhesive layer joining the components, disposed between the components.
In the manufacture of catheters for medical interventions, such as balloon or guide catheters for a percutaneous transluminal angioplasty or placement instruments for implantation of an endoprosthesis, many different materials are used. Primarily plastics are used, such as polyamide, polyimide, polyether ether ketone for catheter shafts, polycarbonate for connectors, nylon or polyethylene terephthalate for dilation balloons and polyurethane for catheter tips, but so are metal materials, such as nickel-titanium alloys for stiffer shaft sections, gold for x-ray impermeable marking rings or stainless steel for stiffening wires. Depending on the physical properties necessary for the function, a suitable material must be selected for each catheter component such that a fully assembled catheter has connection points with extremely varied pairs of materials to be joined. In practical use, some of the connections are exposed to intense mechanical loads and must meet the high safety standard of medical catheter technology. Compared to the attachment of shrink sleeves and welding, the gluing of catheter components is a relatively simple and, consequently, a popular joining technique.
With the large selection of available adhesives, most connections between the components of a catheter can be made quickly and with adequate stability. The adhesion of two catheter components now depends on whether an adhesive is available which, when solidified, forms in addition to the internal cohesive force, forms adhesive forces with the gluing surfaces of the two components to be connected as well. Due to the variety of component materials in terms of their chemical structure, which enables the formation of the adhesive forces, or in terms of their wettability, it happens that no adhesive material bonds adequately solidly with both catheter components at the same time. On the other hand, it is possible that with an adhesive which would bond with both components the hardening process cannot be performed because of structural constraints or would take too much time. For catheter technology, this means a limitation of the selection of materials or the use of connection techniques more expensive than gluing.